Irrigation system



April 12, 1966 R. .1. PURTELL 3,245,595

IRRIGATION SYSTEM Filed Jan. 20, 1964 5 Sheets-Sheet 1 INVENTOR.

April 1966 R. .1. PURTELL 3,245,595

IRRIGATION SYSTEM Filed Jan. 20, 1964 5 Sheets-Sheet 2 8O 88 qo I l I 1 7O 3o 22 I00 I04 l 54 F 46 lO6 26 102 \20 FIG. 2

FIG. IO

IN VENTOR.

RUFUS J. PURTELL April 12, 1966 R. J. PURTELL IRRIGATION SYSTEM Filed Jan. 20, 1964 5 Sheets-Sheet 5 INVENTOR:

April 12, 1966 1 P T 3,245,595

IRRIGATION SYSTEM Filed Jan. 20, 1964 '5 Sheets-Sheet 4 RUFUS J. PURTELL INVENTOR.

R. J. PURTELL IRRIGATION SYSTEM April 12, 1966 Filed Jan. 20, 1964 5 Sheets-Sheet 5 RUFUS J. PURTELL INVENTOR.

United States Patent This invention relates to agricultural irrigation and more particularly to a vehicular system for moving agricultural irrigation sprinkler pipe from one location to another.

Under Rule 78, cross reference is made to my following patent applications which are copcnding with this application:

Serial No: 226,201, filing date: Sept. 26, 1962, now

abandoned Serial No.: 264,507, filing date: March 11, 1963 Serial No.: 331,087, filing date: December 12, 1961 A problem which exists in systems for moving sprinkler pipe is keeping the vehicles in line. These systems are often one thousand three hundred feet in length and by slippage of the wheels in mud or otherwise, often the individual vehicles of the system tend to become misaligned. I have solved this problem by providing a variable speed ratio drive between the rotating shaft by which the vehicles are powered and the wheels on the vehicles themselves. Common, ordinary variable diameter V belt sheaves are used in this variable speed transmission. A turnbuckle-type arrangement is used to vary the diameter of the sheaves as required.

Another problem which has existed is the accumulation of mud upon the wheels of the vehicle. I have solved this problem by providing a loose hoop or band which encircles the wheel and is held in place by the lugs of the wheel. The hoop has flaps of flexible material, such as rubber belting, attached thereto to relieve the mud from the wheel.

It is a desirable practice to have trail tubes extending behind the main sprinkler pipe to discharge water therefrom. When moving, the drag of these trail tubes can overturn the vehicles. Therefore, I have found it de: sirable to attach weights to the vehicles to prevent them from overturning.

Another desirable feature is to provide for disengaging the drive to the wheels in case the vehicles are to be towed behind a tractor moving from one field to the other, or in the event that it is desired to move a particular vehicle by hand.

Another problem with irrigation pipe moving systems is that the entire system sometimes tends to move axially. This axial movement may result from the fact that the system is operating on a hillside with one end lower than the other. Also, this axial movement might result from the fact that it is moving across land where the rows are angled to the direction of movement. In other cases, systems seem to move axially without logical explanation however, it is supposed that the different ground from one end of the system to the other would be the cause of this movement. I have designed a system whereby the wheels can be angled to a very small movement so as to cause the system to be moved straight. Also, this adjustment is desirable inasmuch as sometimes the boundaries of a field deviate slightly from 90 corners. In such a case, it is desirable to have the system move at a slight angle so that it is always in position to be connected to the main supply pipe. I have provided a system which may be adjusted so that the wheels are set at a slight angle to the pipe to either cause the system to move straight on a hillside or to move at angles in case it is desired to do so.

Objects of this invention are to provide a system for moving agricultural irrigation sprinkler pipe which provides the above desirable features and overcomes the above discussed problems.

Further objects are to achieve the above with a device that is sturdy, compact, durable, simple, versatile, and reliable, yet inexpensive and easy to manufacture and operate.

Still further objects are to achieve the above with a method that is rapid, inexpensive, and easy for inexperienced unskilled people to perform.

The specific nature of the invention as well as other objects, uses, and advantages thereof will clearly appear from the following description and from the accompanying drawing, the different views of which are not necessarily to the same scale, in which:

FIG. 1 is a perspective view broken away in parts illustrating a system according to this invention.

FIG. 2 is a section view of one vehicle of the system taken on line 22 of FIG. 3 with parts broken and cut away for the purpose of clarity.

FIG. 3 is a side elevational view of one vehicle of the system with one wheel set for transverse movement and one wheel set for longitudinal movement.

.FIG. 4 is a plan view of a plurality of vehicles somewhat schematic showing the general arrangement of the system.

FIG. 5 is a sectional partial detailed view taken on line 5-5 of FIG. 3.

FIG. 6 is a sectional partial detail view of a portion of the vehicle taken on line 6-6 of FIG. 3.

FIG. 7 is a partial sectional view taken on line 7-7 of FIG. 2. V

FIG. 8 is a partial sectional view taken on line 88 of FIG. 3.

FIG. 9 is a partial sectional view taken on line 9-9 of FIG. 3.

FIG. 10 is a sectional view taken on line 10-10 of FIGS. 3 and 7.

Referring more particularly to the drawings, pipe 10 is adapted to carry water under pressure and discharge this water'through sprinklers 1-2 mounted upon the pipe onto the land to be watered. In addition, trail tubes 14 are attached to the pipe 10 which though the use of connectors 16 have one or more sprinklers 18 whichalso discharge water upon the land to be irrigated.

The pipe It is connected to header pipe 11 which is a source of water under pressure to pipe 10 (FIG. 4). The pipe 10 is adapted to carry water under pressure. Sprinklers 12 and tubes 14 and sprinklers 18 form means for distributing the water upon the land to be irrigated. Means are provided for draining the pipe 10 and the trail tubes 14 as disclosed in my prior applications noted above.

A plurality of vehicles 20 are attached to the pipe 10, supporting the pipe and moving the pipe generally transverse to the longitudinal axis of the pipe to different locations. Each vehicle has frame 22. Clamp 24 upon the frame 22 provides means for clamping the pipe 10 securely to the frame 22 (\FIGS. 1, 2, 3, 5, and 6). Two vertical tubes 26 are attached to the frame 22 symmetrically arranged relative to the clamp 24. A bracket 28 is journalled within each tube 26. Each bracket 28 is in the form of an L shaped shaft which has a vertical leg 30 which is journalled within the tube 26 and a horizontal leg 32 which forms the spindle for ground engaging wheel 34.

The vertical leg 30 has horizontal plate 36 welded thereto near the bottom which forms a stop for the tube 26 on the frame 22.

Two index plates 44 are bolted to the plate 36 (FIGS. 5 and 6). Each index plate 44 has a plurality of notches 42 located in an upturned portion thereof. Arm 45 is attached by welding or otherwise to the bottom of tube 26. Two leaves 38 are pivoted about a horizontal axis =3 to the arm 45. The notches 42 are less than the combined width of the two leaves 38 so-th-at only one leaf may be engaged in a notch at any one time. The bolt about which the leaves 38 are pivoted is mounted about two ears 39 attached to the arm 45 so that the leaves are restrained against lateral movement. By engaging either one or the other of the leaves 38, a very fine adjustment may be made as to the angular direction of the bracket 28 and therefore, a very close adjustment can be made as to the direction the wheels 34 point. As stated in the introduction, the wheels 34 may be set at a small angle to the pipe 10 so as to prevent the pipe from moving axially in case the system is operating on a hillside or to make the system run at a slight angle in case such operation is desired. The index plates44 are attached to the plate 36 .by means of slotted holes 3 7 so they may be adjusted if desired. The wheels 34 may be rotated 90 as shown by the right hand wheel of FIG. 3 so that the vehicle may be moved in an axial direction if such is desired. Le. to move the system from one field to another, the wheels 34 may be moved to a position as shown by theright wheel in FIG. 3 and the entire system moved in an axial direction either by the power shaft 70, as will be explained later, or by a towing tractor.

Pinion 46 is mounted for rotation upon the vertical leg 30 immediately above tube 26 (FIGS. 1, 2 and 3). It mates with gear 48 which is attached to the spokes 5d of each wheel 34. iPinion tube 52 is attached to the top of the pinion 46 and also is journalled for rotation about vertical leg 30. The pinion 46 is longer than the width of the teeth in gear 4-8. As one portion of the pinion 46. becomes worn, the position of the pinion relative to the gear is adjusted by placing washers between the pinion and the tube 26, thereby bringing another portion of the pinion into engagement with the gear 48; Hole 54 is drilled through vertical leg 30 so that if it is desired to maintain the pinion 46 out of engagement with the gear 48, a pin is placed through the hole 54 and therefore, the pin-ion 46 disengaged from the gear 48.

In addition, dog clutch 56 isprovided between the pinion tube 52 and horizontal sheave 5'8 which is mounted for rotation about the vertical leg 30 above the pinion tube5 2 (FIGS. 2, 3, and 7). Pin 60 through the top of the vertical leg 30 prevents the sheave 58 from riding up ward although in general, gravity prevents this. The dog clutch 56 includes a plurality of radial vanes 62 extending from the hub of the sheave 58. Lever 64 is pivoted between ears 66 which are welded to the top of the pinion tube 52.- Spring 68 extends from the lever 64 to the pinion tube 52 in such manner that it holds the lever 64 engaged with the vanes 62 in one position or disengaged in the second position. Thus, I have provided for interrupting the drive train from sheave 58 to wheels 34. The

pinion 46 may be raised from engagement with gear 48 or the lever 64 of dog clutch 56 may be disengaged from the vanes 62 of the sheave 58.

Shaft 70 extends along the pipe 10 immediately below it and extends from one end of the system to the other (FIGS. 1, 2, 3, 8, and 10). The shaft '70 is rotated by conventional means such as a motor which is known to the-art and therefore, are not discussed here. At each vehicle 20, the shaft 78 has two variable diameter sheaves attached thereto. The outer half 72 of each sheave is connected to the shaft 76 as by a set screw through the hub thereof. The inner half 74 of each variable diameter sheave is mounted to move axially along the shaft 70. Two threaded bearings 76 surround the shaft 70 and one end of each threaded bearing 76 bears against one of the inner halves 74 through a thrust bearing 75. Each threaded bearing 76 has a key 78 thereon which fits within a slot with-inhanger 8t). Each of the hangers 80 is attached as by welding to the frame 212 of the vehicle 20. Therefore, the threaded bearings 76 are mounted for axial movement but are restrained so they cannot rotate. V belt 82 is trained around each of the variable diameter sheaves, by one of theidlers 84, around horizontal sheave 5'8, around another idler 8'4, and back to the variable diameter sheave. The idlers 84 are attached to arm 86 which is attached to the frame 22.

Sleeve 88 encircles one end of each of the threaded bearings 76. Pendant 90 extends from the-sleeve 88. The sleeve 88 is threaded with right hand threads on one end and left hand threads on the other. Arm 92 is attached to pipe 10 by clamp 94. Thus, if any vehicle 28 becomes misaligned with the other vehicles, the pipe 10 will bend between the clamp 24 and the clamp 94. This bending of the pipe will be transmitted through arm 92 which is attached to pendant 90 so that as to rotate sleeve 88. Rotation of the sleeve 88 will cause the threaded bearings 76 toexpand or contract. By expand, I mean move away from one another; and by contract, I mean move toward one another. When the threaded bearings 76 exand, they cause the inner half 74 of the variable diameter sheaves to move toward the outer halves '72. This movement increases the effective radius of the sheaves on which the V belt 82 operates. This increase of the diameter causes the belt 82 to move at a faster speed which causes the vehicle 20 to move at a more rapid speed. Misal-ignment of the vehicle which would cause a contraction of the threaded bearing 76 would result in a slowing down of the vehicle 20. Thus, I have provided means to maintain the vehicles 20 in line. This means for aligning includes changing the speed ratio of the gearing between the shaft 70 and the wheels 34. The gearing connecting the shaft and the wheels includes variable diameter sheaves (having the halves 72, 74), the V belt 82, the sheave 58, the dog clutch 56, the pinion 46, and the gear 48. The means for changing the speed ratio includes the variable diameter sheaves. The arm 92 and the clamp 94 form means for detecting if the vehicle 28 is misaligned.

It will be noted that the variable diameter sheaves are self-centering without any direct connection between them, i.e. if the front wheel 34 were to tend to rotate faster than the back wheel 34, the V belt 82 driving the front wheel would have more tensionthan the other inasmuch as the front wheel would be pulling the back wheel and the V belt 82 to the back wheel would tend to become slack inasmuch as the back wheel would not be driving the vehicle 26 forward, but would be merely idling. This greater tension in the front belt 82 would be transmitted through the variable diameter sheave inside half 74 through the threaded bearings 76 to the inner half 74 of the other sheave and inasmuch as the belt 82 on the other sheave would be loose, there would not be so much resistance offered to increase the diameter of said sheave.

As may be seen, frame 22 extends on either side of pipe 10. One side will be designated as the forward side and the other as the rear side although, it will be understood that by reversing the direction of rotation of the shaft 70, the vehicle will travel in the opposite direction. If the vehicles travel in the opposite direction-it is necessary to move the trail tubes 14 around the other way, but in any event, there will always be a forward and rear side of the vehicles 20- depending upon which side the trail tubes are on. Even if the trail tubes 14 are not used, it would be a convenient designation to designate one side as forward and the other as rear. The forward wheel 34 on the forward part of the frame 22 is on one side of the frame when the pipe 10 is moving transversely to its longitudinal extent while the rear wheel 34 is on the opposite side of the frame 22 from the front wheel. Of course, when the system moves transversely to'the pipe 10 the axis of each wheel 34 is parallel to the pipe. The forward wheel rotates clockwise while the rear wheel rotates counter clockwise when viewed from the frame. Therefore, if it is necessary or desirable to move the system in a direction such as parallel to the frame, both wheels may be rotated so that they are in the position with their axis normal to the pipe It and dri en so that one wheel 34. is

driven in a clockwise direction when viewed from the frame 22 and the other wheel is driven in a counter clockwise direction when viewed from the frame.

Also, it will be apparent upon analysis, that if the wheels 34 were both on the same side of the frame, they would both have to rotate in the same direction as viewed from the frame to move the system transversely of the pipe. However, if they were rotated outwardly so that the axes were parallel as viewed from the frame, one would have to rotate in a clockwise direction and the other in a counter clock wise direction as viewed from the frame. By having the wheels on opposite sides of the frame at all times, they may be set to move in any direction or the shaft 70 reversed without the changing of the belts 82.

It is desirable for the vehicles 20 to travel at the same speed. To achieve this and to better achieve alignment, it is desirable that the diameter of all the wheels 34 remain the same. Obviously, to manufacture the wheels 34 the same diameter is an easy task, but if mud accumulates on the wheel, it reaches a larger diameter so that alignment becomes more diflicult. Therefore, relieving mud from the wheels 34 helps to maintain the vehicles in alignment.

I have provided such a mud reliever which includes hoop or band 106) which has a larger diameter than rim 1132 of the wheel 34 (FIGS. 1, 2, 3 and 9). The band 100 is maintained in place by the lugs 104- on the wheel. The lugs 104 are attached in pairs on either side of the band 100 and are spaced peripherally around the rim 102. The diameter of the band 100, while being greater than the diameter of the rim 102, is less than the diameter of the rim and lug 104. Therefore, it may be seen that the band 10!) cannot be removed from the wheel 34. The rim 102 has a central depression 106 extending annularly therearound. This depression is about the same depth and width as the band 100 so that the band 1% will fit within the depression 196 and the outside of the band 10%) is flush with the remainder of the rim 102. A flexible flap 108 is attached to the outer part of the band Hi0 as by riveting between each adjacent set of lugs 104. The flexible flap 1123 is made of rubber belting or similar flexible, pliable material. The width of the fiap 108 is approximately the same as the width of the rim 162. The length of the flap 168 is slightly less than the length between adjacent pairs of lugs 104. As the wheel 34- rotates, on the portion of the wheel 34 at the bottom (as seen in FIG. 9), the band 1% will be within the depression 1% and the flaps 168 will be flat against the rim 102. However, as that particular flap 108 is rotated upward, it will move away from the rim 102. Any mud on the flap 108 will tend to be shaken therefrom inasmuch as mud does not stick to a flexible rubber-like surface as well as it does a rigid steel-like surface. On top (FIG. 2) the flap 108 will be completely separated from the rim 102. Thus, I have provided means for relieving mud from the outside of a ground engaging wheel.

The trailing tubes 14 behind the system increase the drag at the top of the system. If the connector 16 becomes entangled in growing plants, the drag may be so much as to threaten to overturn the vehicle 20. In any event, the weight on the front wheel is reduced to what it is on the back wheel.

I have solved this problem as seen in FIG. 1 by adding a weight 119 to the frame 22 on the forward side of each vehicle 20. This weight has not been shown in the other figures for the purpose of simplifying those representations. The weight 110 consists of a cast block of concrete with a metal hook extending from the top to hook over any convenient portion of the frame 22 on the forward side thereof.

It will be apparent that the embodiment shown is only exemplary and that various modifications can be made 6 in construction, materials, and arrangement within the scope of the invention as defined in the appended claims.

I claim as my invention:

1. In an irrigation pipe moving system having (a) an elongated pipe adapted to carry water under pressure,

(b) a plurality of vehicles attached thereto to move the pipe transversely,

(c) a shaft extending along the pipe, journalled for rotation to the vehicles, and

(d) gearing means interconnecting the shaft and each of the vehicles for moving the vehicles responsive to rotation of the shaft; the improved means for maintaining the vehicles in alignment comprising in combination:

(e) means attached to the vehicles for detecting if a vehicle is misaligned, and

(1") means attached to said gearing means for changing the speed ratio of said gearing means responsive to misalignment as detected by said means for detecting.

2. The invention as defined in claim 1 wherein said means for changing the speed ratio includes (g) a variable diameter sheave connected within the gearing means.

3. In an irrigation pipe moving system having (a) an elongated pipe adapted to carry water under pressure,

(b) a plurality of vehicles attached thereto to move the pipe transversely,

(c) a shaft extending along the pipe, journalled for rotation to the vehicles, and

(d) gearing means interconnecting the shaft and each of the vehicles for moving the vehicles responsive to rotation of the shaft; the improved means for maintaining the vehicles in alignment comprising in combination:

(e) means attached to the vehicles for detecting if a vehicle is misaligned,

(f) means attached to said gearing means for changing the speed ratio of said gearing means responsive to misalignment as detected by said means for detecta (g) each vehicle having at least two ground engaging wheels which are driven by said gearing means, and wherein (h) said gearing means including a V belt for each wheel interconnecting the shaft and its wheel, and wherein (i) said means for changing the speed ratio includes a variable diameter sheave on the shaft for each of said V belts,

(j) an expandable element between the two variable diameter sheaves, and

(k) a link between said means for detecting and said expandable element.

4. In an irrigation pipe moving system having (a) an elongated pipe adapted to carry water under pressure,

(b) a plurality of vehicles attached thereto to move the pipe transversely,

(c) a shaft extending along the pipe, journalled for rotation to the vehicles, and

(d) gearing means interconnecting the shaft and each of the vehicles for moving the vehicles responsive to rotation of the shaft; the improved means for maintaining the vehicles in alignment comprising in combination:

(e) means attached to the vehicles for detecting if a vehicle is misaligned,

(f) means attached to said gearing means for changing the speed ratio of said gearing means responsive to misalignment as detected by said means for detect- 111g,

(ff) said means for detecting misalignment including,

(g) a rigid arm attached to said pipe a spaced distance from the vehicle,

(h) said arm including a shank extending beneath the pipe to the vehicle so that movement of the end of the shank forward relative to the vehicle indicates the vehicle is forward in its alignment with other vehicles and movement of the arm backwards relative to the vehicle indicates a vehicle is behind the other vehicles attached to said pipe.

5. The invention as defined in claim 1 wherein (g) each of said vehicles has two wheels,

(h) each wheel having a broad flat peripheral face,

(i) a plurality of lugs extending radially from either side of a median space on said peripheral face,

(i) a band encircling the wheel (k) in the median space,

(1) the radius of the band is less than the radius of the wheel plus the height of the lugs, and

(m) a plurality of flexible flaps are attached to the band and extend axially therefrom,

(n) said flaps extending between the lugs on either side of the median space on said peripheral face.

6. An irrigation pipe moving system comprising in combination:

(a) an elongated pipe adapted to carry water under pressure,

(b) a plurality of vehicles attached thereto to move the pipe,

(c) a shaft journalled for rotation to the vehicles,

(d) each vehicle having two brackets, each mounted for rotation about a vertical axis,

(e) a ground engaging wheel journalled for rotation to each bracket,

(1:) said ground engaging wheel driven by a pinion engaging a gear attached to said wheel,

(g) said pinion mounted for rotation about the vertical axis of rotation of said brackets,

(h) a tube attached to said pinion extending upward therefrom,

(i) a sheave on top of the tube,

(j) a belt interconnecting the shaft and the sheave for rotating the sheave, and

(k) a dog clutch connecting the sheave to the tube so that the wheel may be manually disengaged from being driven by the rotation of the shaft.

7. The invention as defined in claim 6 with the addition of (1) means attached to each of the vehicles for detecting if said vehicle is misaligned, and

(m) sheaves of variable diameter attached to said shaft to which said variable diameter sheaves said belt is trained, and

(n) means for varying the diameter of said sheaves responsive to said means for detecting misalignment.

8. The invention as defined in claim 6 with the addition of (m) tubes attached to the pipe trailing therebehind, and

(n) a weight attached to the vehicle on the forward side thereof.

9. In an irrigation pipe moving system having (a) an elongated pipe adapted to carry water under pressure,

(b) a plurality of vehicles attached thereto to move the pipe transversely, and

(c) a plurality of tubes trailing behind said vehicle;

the improvement comprising:

(d) each of said vehicles having a frame,

(e) a wheel mounted to the vehicle on either side of the pipe, and

(f) a weight attached to the frame of the vehicle on the side of the vehicle which is on the opposite side of the pipe from which the tubes trail to prevent the vehicles from turning over due to the moment of trailing the tubes.

dition of:

MB. In an irrigation pipe moving system having (a) an elongated pipe adapted to carry water under pressure,

(b) a plurality of vehicles attached thereto to move the pipe transversely, and

(c) a shaft extending along the pipe, journalled for rotation to the vehicles; the improved comprising:

(d) a frame extending on both sides of the pipe,

(e) a forward wheel on the forward part of the frame,

(f) a rear wheel on the rear part of the frame,

(g) the axis of each wheel parallel to the pipe,

(h) the forward wheel extending to one, side of the frame,

(j) the rear wheel extending on the opposite side of the frame from the front wheel,

(k) each Wheel connected to the frame by a bracket,

(in) each bracket rotatably mounted to the frame about a vertical axis so that the axis of each wheel may be positioned normal to the pipe,

(n) means interconnecting the shaft and front wheel for rotating the front wheel clockwise as viewed from the frame responsive to rotation of the shaft in a first direction, and

(0) means interconnecting the shaft and rear wheel for rotating the rear wheel counter clockwise as viewed from the frame responsive to rotation of the shaft in said first direction.

11. The invention as defined in claim 10 with the addition of:

(p) means on the vehicle for detecting if said vehicle is aligned with other vehicles attached to said pipe, and

(q) means attached to each of said means for rotating the wheels for changing the speed ratio between the shaft and wheel responsive to misalignment as detected by said means for detecting.

12. The invention as defined in claim it with the ad- (p) tubes attached to the pipe and trailing behind the pipe, and

(q) weight on the forward part of the frame to prevent the vehicle from turning over while dragging the tubes.

13. In an agricultural irrigation pipe moving system having (a) an elongated pipe adapted to carry water under pressure,

(b) a plurality of sprinklers connected to the pipe for watering the land, I

(c) a plurality of vehicles attached to the pipe for moving the pipe,

(d) at least two ground engaging wheels on each vehicle,

(e) a powered rotatable shaft extending along the pipe,

and

(f) power transmission means on each vehicle for transmitting power from the powered shaft to the ground engaging Wheels; the improvement in combination with the above comprising:

(g) clutch means on each vehicle for disengaging the power transmission means from the powered shaft to each ground engaging wheel.

14. The invention as defined in claim 13 wherein (11) said power transmission means also performs the function of reducing the speed of rotation of the wheels to less than the speed of rotation of the powcred shaft, and

(j) said means for disengaging is located in the power transmission means after at least some speed reduction has been accompiished.

15. In an agricultural sprinkler system having (a) a water supply pipe adapted to have sprinkler means attached at spaced points therealong for dispensing water therefrom,

(b) a pair of frame secured to said pipe at spaced points and each extending ahead of and behind said t p (c) mounting means on each frame for mounting one wheel ahead and one wheel behind said pipe with each mounting means having a vertical wheel supporting axle and having a vertical element journalled in said frame for annular adjustment of each wheel about the vertical axis of one of said vertical element; the improvement in combination with the above comprising:

(d) a powered drive shaft extending along said pipe,

(e) power transmitting means carried by said frames extending from said drive shaft for applying tractive power to each of said wheels,

(f) a multistage speed reducing train, and

(g) clutch means for breaking said train after an initial speed reduction.

16. In an agricultural irrigation pipe moving system having (a) an elongated pipe adapted to carry water under pressure,

(b) a plurality of sprinklers connected to the pipe for watering the land,

(c) a plurality of vehicles attached to the pipe for moving the pipe,

(d) at least two ground engaging wheels on each vehicle,

(e) a powered rotatable shaft extending along the pipe,

and

(f) power transmission means on each vehicle for transmitting power from the driven shaft to the ground engaging wheels; the improvement in combination with the above comprising:

(g) said ground engaging wheels each mounted for rotation about a vertical axis,

(h) said power transmission means performing the function of power transmission regardless of the position of the ground engaging wheels, and

(j) clutch means for disconnecting each ground engaging wheel from the power transmission means so that rotation about the vertical axis is more easily achieved.

17. In an agricultural irrigation pipe moving system having 1t) engaging wheels; the improvement in combination with the above comprising:

(g) said ground engaging wheels each mounted for rotation about a vertical axis,

(h) said power transmission means performing the function of power transmission regardless of the position of the ground engaging wheels, and

(j) means for disconnecting each ground engaging wheel from the power transmission means so that rotation about the vertical axis is more easily achieved,

(k) a portion of said power transmission means aligned with said vertical axis, and

(m) is vertically displaceable to accomplish said disconnection of power transmission.

18. In an agricultural irrigation pipe moving system having (a) an elongated pipe adapted to carry water under pressure,

(b) a plurality of sprinklers connected to the pipe for watering the land,

(c) a plurality of vehicles attached to the pipe for moving the pipe,

(d) at least two ground engaging wheels on each vehicle, and

(e) a powered rotatable shaft extending along the pipe, the improvement in combination with the above comprising:

(f) said ground engaging wheels each mounted for rotation about a vertical axis,

(g) a pinion for each wheel mounted for rotation about the same vertical axis as the wheel,

(h) power transmission means on each vehicle for transmitting power from the powered shaft to the pinion,

(j) each wheel having spokes, and

(k) a gear attached to the spokes of each wheel meshed with the pinion.

19. The invention as defined in claim 18 wherein (m) the pinion is longer than the width of the gear.

References Cited by the Examiner UNITED STATES PATENTS MARVIN A. CHAMPION, Primary Examiner. 

1. IN AN IRRIGATION PIPE MOVING SYSTEM HAVING (A) AN ELONGATED PIPE ADAPTED TO CARRY WATER UNDER PRESSURE, (B) A PLURALITY OF VEHICLES ATTACHED THERETO TO MOVE THE PIPE TRANSVERSELY, (C) A SHAFT EXTENDING ALONG THE PIPE, JOURNALLED FOR ROTATION TO THE VEHICLES, AND (D) GEARING MEANS INTERCONNECTING THE SHAFT AND EACH OF THE VEHICLES FOR MOVING THE VEHICLES RESPONSIVE TO ROTATION OF THE SHAFT; THE IMPROVED MEANS FOR MAINTAINING THE VEHICLES IN ALIGNMENT COMPRISING IN COMBINATION: (E) MEANS ATTACHED TO THE VEHICLES FOR DETECTING IF A VEHICLE IS MISALIGNED, AND (F) MEANS ATTACHED TO SAID GEARING MEANS FOR CHANGING THE SPEED RATIO OF SAID GEARING MEANS RESPONSIVE TO MISALIGNMENT AS DETECTED BY SAID MEANS FOR DETECTING. 